Answer:
-2-10
Step-by-step explanation:
Your answer is 7/40 or 0.175
For this case we have a function of the form:

Where,
A: initial amount
b: decrease rate
x: time in days
Substituting values we have:

Therefore, the graph of the function is a decreasing exponential function in the first quadrant and that has an initial value of 40.
Answer:
graph of exponential function going from left to right in quadrant 1 through the point 0, 40 and approaching the x axis
Check the picture below, you can pretty much count the units off the grid for the length and width.
recall area = length * width.